Status is part of it, but there's a perfectly good statistical explanation too.
There is much higher variance among fat people than among thin people. It's the long tail of the distribution. So plus sizes are much more approximate. It's more likely that the clothes won't fit. This also makes the return on each additional size lower -- there may be a lot of plus-size women generally, but they're spread out enough that there aren't a lot of size 16s specifically.
I don't think that accounts for everything, but it is part of it.
You're already seeing more good plus-size fashion, I think, of necessity. It's coming.
I'm trying to better understand the relationship between incentivization and rationality, and it occurred to me that it is a "folk fact" around here that large financial incentives don't make cognitive biases go away.
However, I can't seem to find any papers that actually say this. It's not easy to google for (I have tried) so I wonder if the Less Wrong collective memory knows how to find the papers?
Is there a pattern to which biases go away with incentivization? Do we have at least 5 examples of biases that go away with incentivization and 5 examples that don't go away with incentivization?
As an incentive, I'll paypal $10 to the commenter whose answer is least biased and most useful.